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Feb. 3, 1931. F. L. SCOTT TIME LI'MI'I VALVE Filed May 24 192 swzzQ/ma v1 is a central vertical Patented Feb. 3, 1931 UNETED STATES FATENT @FFifiE FLOYD L. soccer, or nous/row, TEXAS, AssrGNoR r0 nnenns TOOL COMPANY, or

HOUSTON, TEXAS,

A CORPORATION OF TEXAS TIME-LIMIT vALvE Application filed. May .24,

My invention relates to valves to be placed in fluid-conveying lines to close the passage therethrough after the fluid has acted on the valve for a predetermined time.

The device has its particular application to core drills employed in deep well operations and has, as an object, the provision at the upper end of a core barrel of a valve which will remain open while the lower end of the well is being washed, but which will be closed thereafter) to prevent access of the flushing fluid to the interior of the core barrel while the core is being taken.

It is desired that the valve be closed gradually by the fluid pressure from the pumps, a dash-pot efiect being obtained in limiting the speed of closing so that the well can be washed before closure in eiiected.

It is my aim to provide a structure of this character which is simple and strong in its construction and adapted to function positively without failure in use.

Referring to the drawings herewith, Fig. section through a core drill and barrel with myv valve applied thereto.

Fig. 2-is a similar section of the valve showing the same in closed position.

Fig. 3 is a transverse section on the plane 3--3 of Fig. 1.

Fig. 4 is a transverse section on the plane 4-4 of Fig. 1.

The device is adapted for use on any ordinary type of core drill. I have shown a simple type having a head 1 with its upper end 2 threaded internally to engage the drill stem or collar 9. The interior of the upper shank is reduced in diameter and threaded at 3 to receive the core barrel 8. The lower end of the head is toothed at 4 to cut the bottom of the hole. Above the teeth 4, is a core catcher comprising a sheet metal sleeve 6 with spring fingers 7 Y thereon to engage the core. Longitudinal passages 5 for the flushing fiuid connect the space 10 between the stem 9 and the core barrel 8 with the lower end for discharge of the fluid directly upon the material.

At the upper end of the core barrel 8 is a coupling 11 having a threaded connection with the core barrel and with a guide barrel 1 upon the end of rod 15.

1928. Serial No. 280,347.

12 which extends upwardly in the drill stem. The lower end of the coupling has a plurality of supporting radial spokes 13 connecting with a central hub 1 1 shaped to receive a guide rod 15 secured therein and projecting upwardly in. the guide barrel axially thereof.

The upper end of the coupling 11 has its inner wall tapered upwardly to a seat 16 on the upper rim to receive a valve 17 slidable on the guide rod.

The valve 17 comprises a lower disc 18 of smaller diameter than said guide barrel. It has a ring 19 of compressible material on its lower side to fit upon the seat 16. Said disc has an upwardly-extending sleeve or cylinder 2O centrally thereof to receive a piston 21 Said piston fits loosely in the sleeve or cylinder 20 so that grease or other liquid 22 above the piston can be forced past the piston slowly by pressure. The upper end of the cylinder 20 is slightly enlarged internally ferred to. The upper end of the cylinder is closed by a threaded plug 24.

The valve and cylinder have radial wings above the disc whicli' contact with the interior of the guide barrel and hold the valve and cylinder properly centered in the guide barrel. The upper end of said guide barrel is reduced in diameter at 25 so as to constrict the opening somewhat and limit the upward movement of the valve. 4

In operation, the drill is assembled as shownin Fig. lwith the valve at the upper end of the guide barrel and the cylinder 20 filled with grease or some fluid which flows appreciably only under pressure. Thedrill is then lowered ,to the bottom of the well where the core is to be taken. The fluid in the well. may pass upwardly about the valve as it is lower'ed and when the bottom is reached, the flushing fluid is pumped down through the drill stem to clean out the bottom of ,the hole and the core barrel. The pressure of the fluid upon the valve disc 18 will fore it downwardly to close the valve, but the grease 22 in the cylinder will be forced but slowly past the piston 21, and it will. hence take a predetermined time before the valve is closed.

at 23 as will be laterre- This will allow the well to be thoroughly flushed clear of material before the valve reaches its seat to cut off further flow of fluid through the core barrel.

When the piston reaches the upper end of the cylinder the larger inner diameter 23 of the cylinder will allow free passage around the head of the remainder of the liquid in the cylinder and the valve will close abruptly.

It will be noted that back pressure of liquid from within the core barrel upwardly in use will be possible so that fluid in the barrel may escape as the core moves upwardly to fill the core barrel.

This valve allows the free passage of the drill to the bottom of the hole and will thereafter permit thorough washingof the core barrel and the well bottom before it closes. The advantages of this construction will be apparent to those skilled in the art.

What I claim as new is:

1. In a core barrel, a guide barrel, a coupling connecting said core barrel and said guide barrel, a valve seat at the upper end of said coupling, a valve in said guide barrel of smaller diameter than the said guide barrel, a piston on said coupling, a cylinder on said valve, said piston fitting loosely in said cylinder, whereby liquid in said cylinder may escape slowly past said piston to allow said valve to reach said seat only after a predetermined time.

2. In a core barrel, a guide barrel,-a coupling connecting said core barrel and said guide barrel, a valve seat at the upper end of said coupling, a valve in said guide barrel of smaller diameter than the said guide barrel a piston on said coupling, a cylinder on said valve, said cylinder projecting upwardly from said piston and filled with a viscous liquid, said piston being spaced above said coupling, said piston fitting loosely in said cylinder, whereby liquid in said cylinder may escape slowly past said piston to allow said valve to reach said seat only after a predetermined time.

3. In a device of the character described a drill, a drill stem and a core barrel in said drill stem, in combination with a guide barrel, a coupling connecting said barrels, a valve seat of smaller diameter than said barrels on said coupling, a valve in said guide barrel, shaped to fit said seat, and means to control the movement of said valve to said seat under pressure of flushing fluid unaffected by the rotation of said drill stem.

4. In a device of the character described a drill, a drill stem and a core barrel in said drill stem, in combination with a uide barrel, a coupling connecting said arrels, a valve seat of smaller diameter than said barrels on said coupling, a valve in said guide barrel, shaped to fit said seat, and means on said coupling adapted ,to engage means on said valve to control the movement of said valve to said seat actuated entirely under pressure of flushin fluid.

5. In a device of the character described a drill, a drill stem and a core barrel in said drill stem, in combination with a guide barrel, a coupling connecting said barrels, a valve seat of smaller diameter than said barrels on said coupling, a disc valve in said guide barrel shaped to fit said seat, means to guide said valve in said barrel and means including a piston projecting upwardly from said coupling, a cylinder on said piston shaped to receive said piston loosely, a viscous liquid above said piston in said cylinder so arranged as to control the movement of said valve to said seat under pressure of flushing fluid.

6. In a core drill, a core barrel, a valve seat at the upper end thereof, a valve shaped to fit said seat, a guide above said seat for said v valve, and means, slowly operative entirely by pressure of the flushing fluid to control the movement of said valve into said seat.

7 In a core drill, a core barrel, a valve seat at the upper end thereof, a valve above said seat, means to guide said valve to said seat and means connected with said core barrel, cooperating with means on said valve to retard the movement of said valve to its seat so that it will close only after a predetermined time.

8. In a core drill, a drill stem, a core barrel, a valve seat at the upper end thereof, a valve above said seat, means mounted on said'core barrel and engaging with means upon said valve to retard the closing movement of said valve, said valve being adapted to be moved by fluid pressure independently of the rotation of the said drill or drill stem.

In testimony whereof, I hereunto aflix my signature, this the 7th day of May, A. D.

FLOYD L. SCOTT. 

